Right the ::FFFF::<ipv4-addr> sounds familiar I guess there was also an option that the P router would just label switch the packet towards the exit PE and the PE would than originate the ICMP back to source Or you can turn off TTL propagation across the core -so the ICMP could only time out at the PEs adam -----Original Message----- From: Nagendra Kumar (naikumar) [mailto:naikumar@cisco.com] Sent: Friday, June 15, 2012 12:52 PM To: Daniel Roesen; nanog@nanog.org Subject: RE: IPv6 Lo. for 6PE/6VPE Hi, Per my understanding, it is not required to have ipv6 address in loopback intf on all P routers inorder to have 6PE work. If I remember it correctly, P router will use ::FFFF::<ipv4-addr> while originating ICMPv6 error message. -Nagendra -----Original Message----- From: Daniel Roesen [mailto:dr@cluenet.de] Sent: Friday, June 15, 2012 4:02 PM To: nanog@nanog.org Subject: Re: IPv6 Lo. for 6PE/6VPE On Fri, Jun 15, 2012 at 11:56:05AM +0200, mohamed Osama Saad Abo sree wrote:
I was just wondering , while I'm planning my network to support 6PE/6VPE why should i assign an IPv6 for Loopbacks?
Maybe it's needed for Point-Point links or external interfaces between my peers, but anyone here know why i should assign IPv6 for all my Routers inside my ISP if we will run PE/6VPE not dual stack.
Otherwise the intermediate P devices do not have an address to source ICMPv6 "hop count exceeded" error replies => traceroute doesn't work properly. Best regards, Daniel -- CLUE-RIPE -- Jabber: dr@cluenet.de -- dr@IRCnet -- PGP: 0xA85C8AA0